With the development of information technology, terminal devices have been generally mounted with various communication interfaces. It has become a method for improving transmission efficiency to simultaneously perform transmission of a collaborative service using a plurality of interfaces of a plurality of terminals through cooperation of the terminals so as to achieve an aggregation effect of a plurality of links.
In the transmission oriented to the collaborative service, during the cooperation of the plurality of terminals, a wireless link for cooperation may be affected by co-frequency interference or a channel characteristic and a large amount of data in the link may be lost during the transmission of the collaborative service because of the mobility of terminals for cooperation. Thus, a lost data packet needs to be retransmitted in time in order to ensure sequential transmission of user services. Therefore, various transmission protocols of a transmission layer are all provided with a corresponding rapid retransmission strategy. During the data transmission oriented to the collaborative service, after a collaborative terminal applies for a service, the requested service data is transmitted to each target terminal by a service server via an original path or a switched path. Data retransmission is required if there is data loss. The service server executes a retransmission strategy. A retransmission process is the same as the foregoing data transmission process and a transmission path is shown by a thick solid line in FIG. 1.
With respect to the data retransmission during the transmission oriented to the collaborative service, since there is a relatively long transmission time delay in link transmission, if the retransmission process is the same as the foregoing data transmission process, a transmission path for the retransmission is too long and thus the transmission path and the transmission time delay may reduce the transmission performance to further affect the data transmission efficiency. The aggregation effect brought by the collaborative transmission of the plurality of terminals can be hardly reflected effectively, especially in a data transmission process that requires higher real time.